Faulty ignition coil or coil driver circuit; Damaged, chafed or corroded wiring or connector to the coil; Missing or poor power supply or earth to the ignition coil; Worn spark plugs or damaged plug leads or coil boots placing excess load on the coil; Crankshaft or camshaft position sensor fault affecting ignition timing signals; Internal fault in the engine control unit ignition driver.

P0350

Ignition Coil Primary/Secondary Circuit/Open.

Generic
Powertrain
Generic code
Medium severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
3: AreaIgnition system or misfire
50: FaultThe specific fault in that area

What it means

P0350 is the generic code for a fault in the ignition coil primary or secondary circuit. The engine control unit monitors the coil driver circuits and has detected a signal or feedback that is open, shorted or outside the expected range. It is a general code that does not point to one cylinder, so the exact layout depends on the engine and ignition system fitted.

Symptoms

Engine misfiring, rough running or hesitation
Difficulty starting or long cranking
Engine management warning light on, possibly flashing under misfire
Poor acceleration and reduced power
Higher fuel consumption
Engine stalling or running in a reduced-power mode

Possible causes

Faulty ignition coil or coil driver circuitlikely
Damaged, chafed or corroded wiring or connector to the coillikely
Missing or poor power supply or earth to the ignition coilpossible
Worn spark plugs or damaged plug leads or coil boots placing excess load on the coilpossible
Crankshaft or camshaft position sensor fault affecting ignition timing signalspossible
Internal fault in the engine control unit ignition driverrare

How to diagnose

Read all stored and pending codes and freeze frame data, noting engine load, speed and temperature when the fault set, and check for related misfire or sensor codes
Visually inspect the coil connectors, wiring and earths for damage, heat, moisture, corrosion or rodent chewing
Check the condition of spark plugs, leads and coil boots against the manufacturer's specification
Swap the coil with another cylinder where the layout allows and see whether the fault or any misfire code moves
Test the coil primary and secondary resistance against the manufacturer's figures for that engine
With the connector unplugged, check for the correct power supply and earth, and test the control signal wiring for continuity and shorts
Check the crankshaft and camshaft sensor signals and wiring if the coil and circuit test fine
Only after all other checks, consider the control unit driver, confirming with the manufacturer's procedure

How to fix

Replace the faulty ignition coil, and renew spark plugs at the same time if they are worn
Repair or replace damaged wiring, connectors or terminals in the coil circuit
Restore the correct power supply or earth connection
Replace worn plugs, leads or perished coil boots
Replace a faulty crankshaft or camshaft position sensor if its signal is found to be at fault
Repair or replace the control unit only if testing confirms a driver fault

Can I keep driving?

Medium severity

Short, gentle journeys are possible, but get it fixed soon. A misfire can overheat and damage the catalytic converter, so avoid heavy load and stop if the warning light flashes.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.